Problems with your Mecta 5000Q--Why to Switch to the Thymatron® System IV Now

1. Mecta Spectrum's top stimulus dose is weak. Millicoulomb for millicoulomb the Thymatron® is 42% more effective at inducing seizures than the Mecta (Chanpattana 2001; Swartz 2006). The extra strength of the Thymatron® stimulus helps get effective treatments in older patients and towards the end of longer treatment courses.

2. Mecta's top stimulus dose uses a 1 ms or wider pulsewidth. This is far less efficient than the 0.5 ms pulsewidth of the standard Thymatron® stimulus (Swartz, 2000). If you choose Mecta's 0.5 ms pulsewidth you are limited to half the maximum dose: only 288 mC.

3. It is far too easy to make a mistake setting the Mecta Spectrum stimulus. It has 4 separate knobs that each change stimulus dose. Because each additional knob doubles the chance of an unintended setting, the Mecta Spectrum's 4 knobs make errors 8 times more likely.

4. Are you sure which of the four Mecta knobs to turn to increase or decrease the stimulus dose, and in what order? Mecta's method for doing this is complex, contrived, hard to remember, and without scientific basis. Because just one knob adjusts stimulus dose on the Thymatron®, and a scientifically-based program automatically selects the best frequency and pulsewidth at each setting, you can always be sure of giving the best possible treatment at each dose.

4-Channel Monitor/Printer

The Thymatron® System IV monitors and prints 4 channels (EEG1, EEG2, EKG, EMG), whereas the Spectrum has only a 2-channel printer just like the old SR-1.

Moreover, although an oscilloscopic display creates a "high-tech" appearance, further thought reveals it to be of dubious value because anything displayed on the Spectrum's screen disappears forever before you have had a chance to examine and evaluate it.

Only the Thymatron® System IV automatically tells the doctor when the seizure has ended. In addition to the EEG and EMG endpoint measures of the Thymatron® DGx, the Thymatron® System IV now adds a seizure duration estimate derived from the heart rate, providing unique new information on this critical measure of subcortical ECT response.

Continuous Digital Heart Rate Monitor

Only the Thymatron® System IV monitors and prints digital heart rate each second right on the treatment strip, and also prints the Baseline and Peak Heart Rates—important measures that reflect seizure quality—in the end-of-treatment report.

Only the Thymatron® System IV analyzes and prints out these important manifestations of ECT seizure quality and generalization.

Delivers Maximum Dose with Physiological Pulsewidth

Only the Thymatron® System IV can deliver its maximum dose (504 mC) across the entire dosage rage, using pulsewidths all the way down to Ultrabrief. In contrast, the Mecta Spectrum cannot deliver its maximum dose without using unphysiological pulsewidths of 1 - 2 msec (Mecta Corporation, 1998). In fact, the maximum dose the Spectrum can deliver at its 0.5 ms pulsewidth setting is only 288 mC.

This difference is critically important when giving unilateral ECT to older, high-threshold patients, most of whom will not develop a therapeutically active seizure at maximum dose unless the stimulus is physiologically efficient.

Only the Thymatron® System IV digitizes and stores in memory the complete treatment—including the EEG, EKG, and EMG—thus allowing you to play it back afterwards (e.g., in case the paper ran out during treatment), or send it to a computer for further analysis via the included Genie IV program for EEG data acquisition, processing, and storage.

Power Spectral EEG Analysis

Only the Thymatron® System IV performs a Fast Fourier Transform (FFT), the basis for all digital EEG analysis. Not only can the System IV actually print the power spectral EEG array in the end-of-treatment report if desired, the included Genie IV software and rear-panel RS232 port support a real-time display of all 4 channels of recording on your PC computer screen, with data storage for later analysis.

The Mecta Spectrum has no such capability. Its costly "EEG data analysis" option only allows the user to toggle on or off the printout of the useless "seizure adequacy" measure, described in the News & Notes section of this website.

The Thymatron® System IV therefore has all the functions of a 4-channel digital EEG machine, allowing you to record, store, and analyze EEGs between treatments in order to measure the prognostically-favorable frontal EEG delta activity reported by several investigators (Fink & Kahn, 1957; Roemer et al, 1990-1991; Sackeim et al, 1996) to predict the response to ECT.

Optimized Stimulus Programs

Only the Thymatron® System IV allows the user to select a stimulus parameter combination that maximizes the efficacy for any stimulus dose selected, using either Ultrabrief or 0.5 msec pulsewidth. These programs automatically adjust frequency to maximize stimulus duration, consistent with recommendations from Sackeim’s laboratory (Devanand et al, 1998).

Two studies have shown the greater efficacy of the Thymatron®'s short-pulsewidth, long-duration stimulus compared with the long-pulsewidth, short-duration stimulus of the Mecta (Isenberg et al, 1996; Chanpattana, 2001).

Every Thymatron® System IV includes a genuine EMG monitor—the Mecta Spectrum offers only an extra-cost optical motion sensor that merely reflects gross physical movements, which typically stop while the EMG is still going (Couture et al, 1988).

Worse yet, the Mecta's optical motion sensor can give false movement readings in response to changes in ambient light levels, and if the room is sunny, it may not work at all (MECTA Corporation, 1998).

Single Front-Panel FlexDial for all Choices

Only the Thymatron® System IV has a single "turn-and-press" dial for selection of all stimulus variables and monitoring features—the Mecta Spectrum makes you scan through up to 9 different touchscreens of data, and retains the same 4 dials of the old SR-1 that must be individually adjusted to set the desired stimulus combination.

In contrast, stimulus titration with the Mecta Spectrum requires the operator to set 4 separate knobs for each step in the titration procedure (MECTA Corporation, 1998). Worse yet, because each additional knob doubles the chance of an unintended setting, the Mecta Spectrum's 4 stimulus knobs make errors 8 times more likely.

EEG Ictal Line Seizure Indicator

Only the Thymatron® System IV prints a simple, continuous black line at the top of the strip to show the doctor when the seizure is in progress and when it has ended. No EEG expertise required!

The great reliability of the Thymatron®'s EEG has been confirmed by investigators at several different centers (Swartz et al, 1994; Krystal & Weiner, 1995; Rosenquist et al, 1998).

In contrast, MECTA EEG tracings have been characterized as unreliable by more than one research group (Ries, 1985; Guze et al, 1989).

Change Waveform without Altering Preferred Dose

Only the Thymatron® System IV allows the doctor to adjust pulsewidth, frequency, and duration without altering the desired dose, whereas changing any of these variables on the Spectrum changes the dose. The single dial of the Thymatron® System IV makes dosing fast and easy and reduces the chance of error. In contrast, because each additional knob doubles the chance of an unintended setting, the Mecta Spectrum's 4 stimulus knobs make stimulus mistakes 8 times more likely.

Only the Thymatron® System IV has large L.E.D.s with bright red letters that can be easily read from any angle, which include a timer to instantly show how long the seizure has been going on. The Spectrum’s display is hard to read without bending over directly in front of it.

Instant Impedance Test

Only the Thymatron® System IV lets you test patient impedance and then treat immediately without waiting—the Spectrum can make the doctor wait as long as 10 seconds when it requires a "system override".

The Thymatron® is the most widely-used ECT instrument in the world. In fact, there are many countries (Germany, United Kingdom, Australia, New Zealand, Czech Republic, Denmark, Japan, to name just a few) where the ratio of Thymatrons® to MECTAs exceeds 100 to 1.